The ninth cranial nerve (CN IX), referred to as the glossopharyngeal nerve, includes a branch that innervates the carotid body and carotid sinus. This branch is referred to as the carotid sinus nerve (CSN), which occurs bilaterally (i.e., right CSN and left CSN). The CSN includes afferent fibers that convey information about arterial blood going to the brain. In particular, the CSN conveys chemosensory information and barosensory information. Such information can be useful alone or in conjunction with other information to treat a variety of conditions. Various techniques are described herein for acquisition, analysis and use of CSN information. Such techniques are optionally implemented in conjunction with one or more respiratory, cardiac or metabolic therapies.